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Here is a comparison of natural infiltration with a 30" window cracked 1" compared to 50 cfm of fresh air via a ventilating dehu with the dehu "off". The next couple days have the dehu set down to 45%RH and fresh air on. The impact is clear on the mainfloor, low %RH. The basement was wet with 50 cfm of fresh air and dehu "off". The 50 cfm of fresh air changed the freshness of the home. Perfect conditions with fresh air on and 45% RH. This week providing 50 cfm of fresh air during occupancy. 4:00 PM to 6:00 AM. VS fan "on" with ac set-up to 80^F, 76^F at 4:00 PM, 75^F at 9:30 PM. Raising the %RH setting on the dehu to 53%RH in the basement. The a/c control always reads the %RH 5% less than any of the data loggers. More to follow. Regards TB

Increased the make-up air from 38 cfm to 58 cfm of fresh make-up from 4:00 pm to 6:00 am through the dehu. The dehu operates only during these hours. Cooling load is declining cycling more. VS fan "on" mode. Looking at changing to ""auto" during afternoon/evening hours. Also looking at delaying fresh air ventilation start or different timer cycle. Home air much better with mechanical fresh air as a opposed to natural ventilation through air leaks + 1" x 30" cracked window. Regards TB

July 22-23 is cooler, drier weather. Very little cooling load. The end of this day, the outdoor dew point is close to the desired indoor dew point. The dehu is removing 2-3 lbs. of moisture per hour and indoor dew point is not dropping. This may indicate that much of the 2-3 lbs. per hour of moisture is the moisture load from the structure and occupants. We will know more with lower outdoor dew points this fall. Regards TB